Ferroelectricity‐Enhanced Photocatalysis: Mechanisms, Materials, and Engineering Strategies

Ferroelectric photocatalysts are attracting rapid interest because spontaneous polarization generates internal electric fields that drive directional charge separation under solar illumination. This review demonstrates how switchable polarization, domain configuration, and polarization‐induced band bending govern recombination, transport, and surface selectivity in photocatalysis. We profile representative ferroelectric material systems spanning perovskite oxides and Aurivillius layered phases with compositional tunability, as well as van der Waals (vdW) two‐dimensional (2D) semiconductors. These materials are further enhanced via polarization engineering, which we organize into three categories. First, domain and defect engineering intensify the internal electric field and prolong carrier lifetime. Second, interlayer engineering and heterojunction design translate bulk polarization into interfacial driving forces. Third, multiple coupling reinforces operation with piezoelectric and pyroelectric inputs with emerging opportunities in spin–polarization coupling. We conclude by highlighting the remaining challenges in interfacial stability, domain retention during cycling, and cross‐study comparability. To bridge laboratory advances with practical implementation, we propose a quantitative framework that correlates in situ surface potentials, band offsets, and time‐resolved carrier dynamics to extract an effective internal electric field. Such an approach provides a unified metric for benchmarking polarization strength and guiding the design of durable, programmable ferroelectric photocatalytic platforms.